29571-13-9Relevant academic research and scientific papers
Addition and cyclization reactions in the thermal conversion of hydrocarbons with an enyne structure, 7. - Cycloisomerization of 1-phenyl-1- buten-3-yne to naphthalene via cinnamylidene carbenes - A complex reaction involving 1,2-C switches and 1,2-styryl migrations
Schulz, Kathrin,Hofmann, Jo?rg,Zimmermann, Gerhard
, p. 3407 - 3412 (2007/10/03)
The thermal conversion of [4-13C,4-D]- (1) and [4-13C]-1-phenyl-1- buten-3-yne (7) has been studied in a quartz tubular reactor at 650 °C (1, in the presence of N2 and N2/toluene, respectively) and at 600 and 620 °C (mixture of 1 and 7, in N2 only) at a reaction time of approximately 0.3 s. The liquid pyrolyzates were analyzed spectroscopically. By means of a special calculation method reported recently, the naphthalene isotopomers formed by reaction pathways other than those proceeding via cinnamylidene carbenes were arithmetically eliminated and the reaction events proceeding via carbene intermediates were mechanistically analyzed. The result of this analysis undoubtedly suggests a complex reaction in which the rates of the partial reactions may be placed in the following order: 1,2-D(H) >> 1,2-styryl > 1,6- C,H.
Thermal Azulene Rearrangements. Synthesis and Thermolysis of Azulene
Gugel, Hansjoerg,Zeller, Klaus-Peter,Wentrup, Curt
, p. 2775 - 2784 (2007/10/02)
A specific synthesis of azulene (24) is described.The synthetic sequence outlined in scheme 3 begins with the construction of toluene (17) which is performed in 8 steps starting from paraformaldehyde.The suspected scrambling of the label in the dehydrogenation step 16 -> 17 can be suppressed by suitable reaction conditions.After extension of the side chain by 3 carbon atoms to give 1-diazo-4-(phenyl)-2-butanone (21), the labelled azulene is obtained according to Scott's azulene synthesis (21 -> 22 -> 23 -> 24).The vacuum thermolysis of24 (1050 deg C, 10-3 - 10-2 torr) yields naphthalene (25) as the main product (91 percent of the naphthalene formed) in accordance with the norcaradiene-vinylidene mechanism.The remaining 9 percent consist of naphthalene.Besides the formation of naphthalene (15 percent conversion), 24 suffers automerisation to a small extent yielding - and azulene (ca. 3 and 1 percent, respectively).
CO2 Laser-induced Rearrangement of Azulene to Naphthalene
Scott, Lawrence T.,Kirms, Mark A.,Earl, Boyd L.
, p. 1373 - 1374 (2007/10/02)
The first rearrangement of an aromatic compound to be induced by i.r. radiation is reported and has been used to provide evidence against the involvement of wall effects in the conventional thermal rearrangement of azulene to naphthalene.
